In silicon wafer manufacturing processes, the surfaces of silicon wafers that have been cut from a silicon ingot drawn up by the CZ (Czokralski) method or the like are finished to a mirror surface state by a lapping treatment using a polishing liquid containing a polishing agent that has a fine particle size.
Then, after passing through a cleaning process, the surfaces of the silicon wafers that have been subjected to such a surface finishing treatment are inspected visually by a worker, and only wafers in which no scratches or staining are observed are shipped as satisfactory wafers.
In the case of visual inspection of the wafer surfaces by a human being, the methods and judgement criteria used have not been standardized, so that such procedures are inadequate in terms of enhancing the degree of customer satisfaction.
The present invention was devised in light of such problems; a first object of the present invention is to provide a wafer surface inspection device and method which allow the reliable detection of scratches and staining that are cause for a judgement of “defective”.
Furthermore, a second object of the present invention is to provide a defective wafer judgment device and method which allow the reliable detection of scratches and staining that are cause for a judgement of “defective” in accordance with characteristic quantities relating to these scratches and staining.
Furthermore, a third object of the present invention is to provide a wafer surface information processing device which accumulates wafer surface information and provides this information for use in wafer treatment processes and other processes.
It is convenient to be able to grasp the types of scratches and haze occurring on the surfaces of wafers in various processes such as wafer treatment processes, conveying processes and the like. This makes it possible to make accurate modifications in various, and is also useful in the planning of modifications and the like.
Furthermore, if mutual understanding of intentions between the wafer supplier (wafer maker) and user is facilitated, the wafer supplier can supply wafers with a quality that accurately meets the requirements of the user, and the user can easily communicate his own requirements to the wafer supplier.
The present invention was devised in light of the abovementioned problems; a fourth object of the present invention is to provide a system which is devised so that trends in the occurrence of scratches and haze in specified processes can easily be detected, and information concerning these trends can be freely exchanged between wafer suppliers and consumers.